Bioelectricity beats biofuels – if you’re driving

Premise: The quantity of land available to grow biofuel crops withoutimpacting food prices or greenhouse gas emissions from landconversion is limited. Therefore, bioenergy should maximizeland-use efficiency when addressing transportation and climatechange goals. Biomass could power either internal combustionor electric vehicles, but the relative land-use efficiency ofthese two energy pathways is not well quantified.

A paper published yesterday in Science concludes that, from a sustainability point of view, using biomass to produce electricity for electric vehicles would produce 81% more transportation (miles driven) than using the same amount of biomass to produce ethanol for internal combustion engines. The researchers also conclude that the electricity option has greater potential for reducing CO2 also. Results are summarized in a poster here.

The researchers reached their conclusions after conducting a life-cycle analysis of bioelectric and bioethanol technologies. The analysis took into account not only the energy produced by each technology but also the energy consumed in producing the vehicles and fuels.

Part of the reason, as reported in today’s ScienceNow summary, is that electric engines are far more efficient than internal combustion engines, and other factors also must be considered. If only complex problems could have simple answers! –nks